CRISPR: Could it Change Evolution? - Tom D., Alexandre R., Chi-Yu H., Ines V. Recently, there has been a lot of debate surrounding the rise of genetically modified organisms and their possible implications. Genetic modification using the CRISPR-Cas9 protein can greatly advance our medical care as it has the potential to cure genetic diseases such as cystic fibrosis and cancer. However, genetic engineering faces many challenges that must be addressed before it can reach its full implementation.
The idea of CRISPR came from microbiology. A common belief is that bacteria and viruses are bad for people, but few people know that there is a type of virus that infects bacteria called bacteriophages. By injecting its genome into the bacteria, the bacteriophage uses the microbe to reproduce, killing it in the process.
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Very few women have gotten a Nobel Prize in chemistry since its invention, only 5 actually, out of 183 winners. The fact that two women have gotten the Nobel for their work and are recognised for it, as sometimes men took all the credit for them, shows a leap towards a more gender-equal scientific community. The two women who discovered CRISPR have different nationalities: Emanuelle Charpentier is French and Jennifer Doudna is American. Furthermore, since they have won the Nobel Prize together with different nationalities, it promotes the idea of a growing international scientific community. Our era is defined by glohow a bacteriphage infects a becterium balization and this award reflects that very well. Their scientific discovery unleashed a whole new world of In 1987, a Japanese molecular biologist called Yoshizupossibilities for genetics. mi Ishino discovered CRISPR, or Clustered Regularly Interspaced Short Palindromic Repeats while studying E. coli from the large intestine. While studying them, he found a strange phenomenon (now known as CRISPR): repeating arrangements of base pairs in their DNA. The reason why this is unusual is that the same arrangements define the same characteristics, thus it seemed like a wasted space on the genome. It turns out that this phenomenon is also present in other bacteria and people didn’t know why until 2005. That is when a French scientist, Rodolphe Barrangou, devised an experiment where he put fresh bacteria up against bacteriophages. Unsurprisingly, most of the bacteria died, but the scientist studied the few that DNA is short for deoxyribonucleic acid survived and found that repeating patterns occurred Firstly, let’s define what a gene is. The smallest unit of again. After more research, he came up with the conlife is a cell, and within these cells, they are DNA mol- clusion that these repeating patterns called CRISPR ecules (or deoxyribonucleic acid). DNA has a double were actually caused by the bacteriophages. helix structure with the following base pairs A, C, T, and G: A pairs with T, and C with G. A specific se- How are bacteriophages and CRISPR related? Well, quence of base pairs codes for a gene that defines a bacteria have a defense mechanism: when one surcertain characteristic (red hair, big eyes, etc). vives a bacteriophage attack, it will snip a strand of
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